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fix page alloc

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And add some test for it
This commit is contained in:
Mathieu Maret 2018-11-09 16:30:42 +01:00
parent 4e93b8c26b
commit a7b6139f06
2 changed files with 47 additions and 6 deletions
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12
core/mem.c
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@ -8,10 +8,10 @@ static struct mem_desc *used_page;
static unsigned long bottom_mem;
static unsigned long top_mem;
int memSetup(unsigned long upper_mem)
{
printf("Free Mem going from %d to %d\n", &__ld_kernel_end, upper_mem * 1024);
printf("Free Mem from %d to %d\n", &__ld_kernel_end, upper_mem * 1024);
// Memory description is stored after the kernel. We need some place to store it
unsigned long memdesc_end =
(unsigned long)page_desc +
((upper_mem) / (PAGE_SIZE / 1024)) * sizeof(struct mem_desc);
@ -19,7 +19,7 @@ int memSetup(unsigned long upper_mem)
list_init(free_page);
list_init(used_page);
bottom_mem = lastUsed;
top_mem = upper_mem;
top_mem = upper_mem * 1024;
for (uint i = 0; i < (upper_mem / (PAGE_SIZE / 1024)); i++) {
struct mem_desc *mem = &page_desc[i];
if (i < lastUsed) {
@ -38,15 +38,16 @@ struct mem_desc *addr2memDesc(unsigned long addr)
{
if (addr > top_mem || addr < bottom_mem)
return NULL;
int idx = addr >> PAGE_SHIFT;
return page_desc + idx;
}
unsigned long allocPage(void)
{
if (list_is_empty(free_page))
if (list_is_empty(free_page)) {
return (unsigned long)NULL;
}
struct mem_desc *mem = list_pop_head(free_page);
mem->ref = 1;
list_add_tail(used_page, mem);
@ -61,6 +62,7 @@ int unrefPage(unsigned long addr)
}
mem->ref--;
if (mem->ref == 0) {
list_delete(used_page, mem);
list_add_tail(free_page, mem);
}

41
tests/test.c
View File

@ -1,7 +1,46 @@
#include "list.h"
#include "mem.h"
#include "serial.h"
#include "vga.h"
void run_test(){
static void testPhymem()
{
printf("Testing memory PHY\n");
struct mem_desc *allocated_page_list;
struct mem_desc
*page; // Cast in mem_desc to use it. In fact it's the addr of 4K free memory
list_init(allocated_page_list);
int allocCount = 0;
int freeCount = 0;
while ((page = (struct mem_desc *)allocPage()) != NULL) {
page->phy_addr = allocCount;
allocCount++;
list_add_tail(allocated_page_list, page);
}
printf("%d pages allocated\n", allocCount);
while ((page = list_pop_head(allocated_page_list)) != NULL) {
if (page->phy_addr != (ulong)freeCount) {
printf("Error page %d modified\n", (ulong)page);
}
if (unrefPage((ulong)page)) {
printf("Failed to free page %d\n", (ulong)page);
}
freeCount++;
}
printf("%d pages freed\n", freeCount);
if ((page = (struct mem_desc *)allocPage()) == NULL) {
printf("Error ! Cannot allocate memory\n");
} else {
unrefPage((ulong)page);
}
}
void run_test()
{
testPhymem();
printf("Testing Serial");
serialWrite('h');
serialWrite('e');